Given the heads of two singly linked-lists headA and headB, return the node at which the two lists intersect. If the two linked lists have no intersection at all, return null.

The test cases are generated such that there are no cycles anywhere in the entire linked structure.

Note that the linked lists must retain their original structure after the function returns.

Examples

Example 1

Input:  intersectVal = 8, listA = [4,1,8,4,5], listB = [5,6,1,8,4,5], skipA = 2, skipB = 3
Output: Intersected at '8'

The intersected node's value is 8

Example 2

Input:  intersectVal = 0, listA = [2,6,4], listB = [1,5]
Output: null

The two lists do not intersect

Constraints

• The number of nodes of listA is in the range [0, 3 * 10^4]
• The number of nodes of listB is in the range [0, 3 * 10^4]
• 0 <= Node.val <= 10^5

How the tests work: skipA/skipB say where the lists join; they are only used to build the input. The answer is the value of the node you return, which must be the shared node itself.